Can 10 Cents Be Equal To 15,000 Dollars? A Case Against Open-Artery Hypothesis? Lest We Forget: Message From OAT Trial

Many acute heart attacks are caused by complete shut down of blood supply (due to blockage of a heart artery) to a part of the heart. The heart muscle without blood supply for more than a few minutes can be damaged permanently. Because of this, earliest possible reestablishment of blood flow by opening the closed heart artery is the centerpiece of management of heart attack victims. The time is of the essence in these cases. The prevailing literature seems to be quite clear thus far. It tends to get murky from here on.

What about a patient who does not really come with a heart attack but is found to have a closed artery that might have closed days, weeks, months or years back? There have been some non-randomized trials that suggest that a closed artery should be opened regardless of how long it has been closed. This is the basis for open-artery hypothesis. Simply put, open-artery hypothesis presumes that an open heart artery is better than a closed artery regardless of consideration for most other factors. In addition to some research supporting this hypothesis, it also appeals to our psyche. Broken glass needs fixing; a broken plane engine needs fixing; a broken door knob needs replacing, and a closed artery needs opening. The human body is a complex interplay of several dynamic intangibles (hormones, chemical reactions not visible to the naked eye and so hard to grasp sometime) that a glass, plane or door knob is not. So inductive reasoning may not apply to opening any closed artery.

A study published in December 7, 2006 issue of New England Journal of Medicine (NEJM) studied the benefits of opening a closed artery 3 to 28 days after a heart attack. This randomized study is named occluded artery trial (OAT).This study included the patients who had a heart attack due to a blocked artery, but that artery could not be opened within a few hours for some reason. This study showed that opening the closed artery more than several hours after heart attack not only did not help, but showed a trend toward hurting the patients. This study seems to question the open-artery hypothesis. Hillis and Lange, the authors of an accompanying editorial say that giving beta blockers could be as good as or better than opening a closed artery late after heart attack. Having researched this issue themselves, these authors speak from a position of authority. Increased risk of complications from an invasive stent procedure not withstanding, can a 10 cent beta blocker pill be as good as or better than a 15,000 dollar stent procedure?

After reading this article, I could not help but think of hormonal replacement for post- menopausal females. We had observed that risk of blockages of heart arteries in case of females was much higher after menopause. The obvious difference between pre and post-menopausal women is lack of hormones in post-menopausal women. So replacing those hormones should decrease chances of heart disease in post-menopausal women. It appealed to our psyche. It all made sense! The observational studies seemed to show what we expected. Then came a well-designed trial called HERS (Heart and Estrogen-Progestin Replacement Study) that studied the impact of hormones on heart disease in case of post-menopausal females. It showed that hormone replacement therapy might actually have harmful effects.

Could there be a parallel between hormone replacement therapy and open-artery hypothesis there?

OAT trial discussed above has sent an important message. From here on, we need to do more to test open-artery hypothesis aggressively. Proving it will validate our present position. Disproving it will not only save our patients numerous potentially harmful procedures, but will also save us much needed health care dollars.
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How to Increase Good Cholesterol (HDL)? Unfortunate Demise of the Pfizer Drug

HDL is an acronym for high density lipoprotein. It is also called good cholesterol. It can be measured by doing a fasting blood test called lipid profile. HDL acts as a friendly scavenger, so higher HDL is protective against blockage of heart arteries. Low HDL is a strong predictor of blockages of heart arteries. The desirable level for HDL is 40 or above. One of the reasons that we tend not to be very aggressive about increasing HDL is that we do not have many easy and good options to deal with this problem.
Few years ago, a study published in the Journal of American Medical Association talked about Apo A-1 Milano that had caused regression of coronary artery disease (blockages in the heart arteries). This was great news. Short of curing the problem of blockages in the heart arteries, having something like a Drano for the heart arteries will be the most important development in the field of cardiology. Around the time of publication of that study, I had Dr. P. K. Shah, an authority on Apo A-1 Milano on my radio show.
Pfizer came pretty close to filling the need for an HDL enhancing drug. Unfortunately, their drug Torcetrapib recently had to be taken out of contention due to excessive deaths among research volunteers taking this medicine.
So what are the measures that can increase HDL?
1. Aerobic exercises like walking, swimming, bike riding and jogging.
2. Weight loss.
3. Smoking cessation.
4. Cutting ingestion of trans fats can increase HDL. Trans fats are found in abundance in fats that are solid at room temperature. The fats described as “hydrogenated oils” on the food packages have lots of harmful trans fats. New York City recently took the lead in banning use of trans fats in the city restaurants.
5. One or two drinks of alcohol daily can increase HDL. There is however, a down side to prescribing alcohol as an HDL enhancing measure. One of the possible problems is alcohol’s addiction potential.
6. There are good fats and there are bad fats. The good kind monounsaturated fats such as canola oil, avocado oil, olive oil and those found in peanut butter can help increase HDL. A word of caution: very low fat diets are known to lower HDL and too much of any fat increases calorie content which can lead to weight gain. The later in turn can decrease HDL.
7. Fibers found in oats, fruits, vegetables and legumes can help increase HDL.
8. The statins like Pravastatin, Simvastatin, Lovastatin, Crestor and Lipitor as a general rule are not good HDL enhancers. High doses of a B group vitamin called Niacin can help increase HDL. The patient acceptance however continues to be a challenge due to side effects like flushing and itching after taking this drug. Some tips on decreasing the chance of side effects from niacin are: taking an aspirin 30-60 minutes before taking niacin, taking niacin at night and avoiding high fat diet at night. Some long-acting niacin manufacturers claim fewer side effects as compared to short-acting niacin.
I am discouraged by the news of unfortunate demise of a promising HDL enhancing drug from Pfizer. But I am very happy to see oversight of research trials (that should assure safety of research volunteers) at work. I think a good, effective and well tolerated HDL enhancing drug will lead to a new phase of aggressive management of low HDL. Short of that, we should focus hard on HDL enhancing measures stated above. All these measures are not only good for increasing good cholesterol, but are also good for our overall wellbeing.
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